patplex: Replace the `default' handling with arbitrary priorities.

diff --git a/doc/patplex.doc b/doc/patplex.doc
index 86d6ace..5a60e96 100644 (file)
--- a/doc/patplex.doc
+++ b/doc/patplex.doc
@@ -92,10 +92,14 @@ rules are recognized:
        'HEADER', the rule never matches. If 'FLAGS' contain the
        character `i`, 'REGEX' is matched case-independently.
 
+*all*::
+
+       The rule always matches.
+
 *default*::
 
-       Matches if and only if no *match* stanza without a *default*
-       rule has matched.
+       Convenient shorthand for an *all* line followed by *priority
+       -10* (see below).
 
 In addition to the rules, a *match* stanza must contain exactly one
 follow-up line specifying the action to take if it matches. Currently,
@@ -109,6 +113,20 @@ only the *handler* action is recognized:
 Additionally, a *match* stanza may contain any of the following,
 optional lines:
 
+*priority* 'INTEGER'::
+
+       Specifies the priority for the match stanza. In case more than
+       one stanza match a request, the one with the highest priority
+       is used. In case more than one stanza with the same highest
+       priority match a request, it is unspecified which will be
+       used. Match stanzas without a priority specification will
+       default to priority 0. Either positive or negative priorities
+       may be specified.
+
+*order* 'INTEGER'::
+
+       A synonym for *priority*. Use whichever you like the best.
+
 *set* 'HEADER' 'VALUE'::
 
        If the *match* stanza as a whole matches, the named HTTP

diff --git a/src/patplex.c b/src/patplex.c
index 9939543..f76cc72 100644 (file)
--- a/src/patplex.c
+++ b/src/patplex.c
@@ -24,6 +24,7 @@
 #include <errno.h>
 #include <ctype.h>
 #include <regex.h>
+#include <limits.h>
 #include <sys/wait.h>
 
 #ifdef HAVE_CONFIG_H
@@ -41,7 +42,6 @@
 #define PAT_METHOD 2
 #define PAT_HEADER 3
 #define PAT_ALL 4
-#define PAT_DEFAULT 5
 
 #define PATFL_MSS 1
 #define PATFL_UNQ 2
@@ -69,6 +69,7 @@ struct pattern {
     char *childnm;
     struct rule **rules;
     char *restpat;
+    int prio;
 };
 
 static struct config *gconfig, *lconfig;
@@ -237,7 +238,14 @@ static struct pattern *parsepattern(struct cfstate *s)
        } else if(!strcmp(s->argv[0], "all")) {
            newrule(pat)->type = PAT_ALL;
        } else if(!strcmp(s->argv[0], "default")) {
-           newrule(pat)->type = PAT_DEFAULT;
+           newrule(pat)->type = PAT_ALL;
+           pat->prio = -10;
+       } else if(!strcmp(s->argv[0], "order") || !strcmp(s->argv[0], "priority")) {
+           if(s->argc < 2) {
+               flog(LOG_WARNING, "%s:%i: missing specification for `%s' directive", s->file, s->lno, s->argv[0]);
+               continue;
+           }
+           pat->prio = atoi(s->argv[1]);
        } else if(!strcmp(s->argv[0], "handler")) {
            if(s->argc < 2) {
                flog(LOG_WARNING, "%s:%i: missing child name for `handler' directive", s->file, s->lno);
@@ -394,7 +402,19 @@ static void qoffsets(char *buf, int *obuf, char *pstr, int unquote)
     }
 }
 
-static struct pattern *findmatch(struct config *cf, struct hthead *req, int trydefault)
+struct match {
+    struct pattern *pat;
+    char **mstr;
+    int rmo;
+};
+
+static void freematch(struct match *match)
+{
+    freeca(match->mstr);
+    free(match);
+}
+
+static struct match *findmatch(struct config *cf, struct hthead *req, struct match *match)
 {
     int i, o;
     struct pattern *pat;
@@ -407,6 +427,8 @@ static struct pattern *findmatch(struct config *cf, struct hthead *req, int tryd
     
     mstr = NULL;
     for(pat = cf->patterns; pat != NULL; pat = pat->next) {
+       if(match && (pat->prio <= match->pat->prio))
+           continue;
        rmo = -1;
        for(i = 0; (rule = pat->rules[i]) != NULL; i++) {
            rx = NULL;
@@ -451,27 +473,32 @@ static struct pattern *findmatch(struct config *cf, struct hthead *req, int tryd
                    }
                }
            } else if(rule->type == PAT_ALL) {
-           } else if(rule->type == PAT_DEFAULT) {
-               if(!trydefault)
-                   break;
            }
        }
        if(!rule) {
-           if(pat->restpat) {
-               exprestpat(req, pat, mstr);
-           } else if(rmo != -1) {
-               replrest(req, req->rest + rmo);
-           }
-           if(mstr)
-               freeca(mstr);
-           return(pat);
-       }
-       if(mstr) {
-           freeca(mstr);
-           mstr = NULL;
+           if(match)
+               freematch(match);
+           omalloc(match);
+           match->pat = pat;
+           match->mstr = mstr;
+           match->rmo = rmo;
        }
     }
-    return(NULL);
+    return(match);
+}
+
+static void execmatch(struct hthead *req, struct match *match)
+{
+    struct headmod *head;
+    
+    if(match->pat->restpat)
+       exprestpat(req, match->pat, match->mstr);
+    else if(match->rmo != -1)
+       replrest(req, req->rest + match->rmo);
+    for(head = match->pat->headers; head != NULL; head = head->next) {
+       headrmheader(req, head->name);
+       headappheader(req, head->name, head->value);
+    }
 }
 
 static void childerror(struct hthead *req, int fd)
@@ -484,44 +511,33 @@ static void childerror(struct hthead *req, int fd)
 
 static void serve(struct hthead *req, int fd)
 {
-    struct pattern *pat;
-    struct headmod *head;
+    struct match *match;
     struct child *ch;
     
-    pat = NULL;
-    if(pat == NULL)
-       pat = findmatch(lconfig, req, 0);
-    if(pat == NULL)
-       pat = findmatch(lconfig, req, 1);
-    if(gconfig != NULL) {
-       if(pat == NULL)
-           pat = findmatch(gconfig, req, 0);
-       if(pat == NULL)
-           pat = findmatch(gconfig, req, 1);
-    }
-    if(pat == NULL) {
+    match = NULL;
+    match = findmatch(lconfig, req, match);
+    if(gconfig != NULL)
+       match = findmatch(gconfig, req, match);
+    if(match == NULL) {
        simpleerror(fd, 404, "Not Found", "The requested resource could not be found on this server.");
        return;
     }
     ch = NULL;
     if(ch == NULL)
-       ch = getchild(lconfig, pat->childnm);
-    if(gconfig != NULL) {
-       if(ch == NULL)
-           ch = getchild(gconfig, pat->childnm);
-    }
+       ch = getchild(lconfig, match->pat->childnm);
+    if((ch == NULL) && (gconfig != NULL))
+       ch = getchild(gconfig, match->pat->childnm);
     if(ch == NULL) {
-       flog(LOG_ERR, "child %s requested, but was not declared", pat->childnm);
-       simpleerror(fd, 500, "Configuration Error", "The server is erroneously configured. Handler %s was requested, but not declared.", pat->childnm);
+       flog(LOG_ERR, "child %s requested, but was not declared", match->pat->childnm);
+       simpleerror(fd, 500, "Configuration Error", "The server is erroneously configured. Handler %s was requested, but not declared.", match->pat->childnm);
+       freematch(match);
        return;
     }
     
-    for(head = pat->headers; head != NULL; head = head->next) {
-       headrmheader(req, head->name);
-       headappheader(req, head->name, head->value);
-    }
+    execmatch(req, match);
     if(childhandle(ch, req, fd, NULL, NULL))
        childerror(req, fd);
+    freematch(match);
 }
 
 static void reloadconf(char *nm)